International Journal of Comparative Psychology

Responsiveness to ethanol is markedly affected by fetal or infantile experiences with the drug. Yet, there is minimal information available relative to the interaction of these experiences. This study focused on such interaction and on the impact of ethanol intoxication on maternal care. Water or subnarcoleptic doses of ethanol were administered to pregnant rats during late gestation (2.0 g/kg) and/or while nursing (2.5 g/kg). Infantile intake of a low concentrated ethanol solution (0.22% v/v) was assessed during postpartum days (PPDs) 15 and 16. Following the first intake test, infantile intake was explicitly paired with water or varying ethanol doses (0.5, 1.0, or 2.0 g/kg) to assess possible associative learning comprising ethanol’s sensory and unconditioned properties. The interaction between ethanol pre- and postnatal treatment resulted in heightened ethanol reactivity as assessed through intake scores, particularly during PPD 16. Maternal treatments failed to affect associative learning mediated by ethanol. Ethanol was also found to disrupt both maternal retrieval and crouching latencies. This effect was markedly reduced when females had experienced ethanol during gestation, a phenomenon indicative of tolerance. Sequential experience with ethanol during gestation and nursing facilitates subsequent responsiveness to minimal ethanol concentrations, without affecting the sensitivity to the unconditioned effects of the drug as evaluated through associative learning procedures.